1. Field of the Invention
The present invention generally relates to motorized vehicles, and more particularly to concrete power buggies.
2. Background Information
As disclosed in U.S. Pat. No. 4,645,264, the teachings of which are hereby incorporated by reference, concrete construction and other work requiring on-the-job transport of heavy materials from one location to another has brought about the development of a variety of relatively-small, load-carrying vehicles capable of moving on the job site with relatively small but often very heavy loads of material. For example, a frequent need is to load a quantity of concrete at a first location, transport such concrete to a second location and then dump the contents for spreading and screeding operations at the second location.
In concrete work, such a vehicle is often referred to as a "concrete buggy." Such vehicles may also be referred to as a dump truck or power-driven wheelbarrow. Some of such vehicles are of the walk-behind type while others are of the step or seat-riding type. The load which is carried by a container called a "skip," "hopper," "pan," or "dump box" is conventionally raised and lowered by a hydraulic piston as in U.S. Pat. Nos. 2,424,670 or 2,427,132. A front pair of single or dual wheels is conventionally driven by a differential and transmission as in U.S. Pat. No. 2,427,132.
Other vehicles have trinary wheel means wherein two separate front wheel means each having single or dual wheels proceed a solitary single or dual rear wheeled means. Typically, the solitary wheeled means supports the rear of the vehicle and is adapted for rotating around a vertical axis for the purpose of steering the vehicle and sometimes with use of a steering mechanism as in U.S. Pat. No. 2,427,132, while the front wheel means supports the front of the vehicle. The trinary-type vehicle is also shown in U.S. Pat. Nos. 4,986,387 and Pat. No. Re. 333,131.
Other patents describe vehicles with trinary wheel means having a powered solitary rear wheel means, including U.S. Pat. No. 2,674,328 (Searls), U.S. Pat. No. 2,820,524 (Bear), U.S. Pat No. 2,942,677 (Gray), and U.S. Pat. No. 3,826,326 (Blair).
However, none of these patents describe a motorized dump-type vehicle having powered front wheels and the ability to engage the vehicle's rear wheel(s) when needed for added traction or control.
A concrete buggy which is filled with concrete tends to have a center of gravity shifted towards the center of the vehicle, towards the front wheels of the buggy. After the buggy dumps its load of concrete, this center of gravity shifts rearward, towards the rear wheel(s) and engine of the buggy. This shift of the center of gravity leaves the front end light, occasionally causing problems in getting traction with the front wheels, particularly where the soil is wet, loose or sandy.
It is one object of the present invention to provide a motorized dump-type vehicle for on-the-job transporting of concrete or other materials, the vehicle having at least two powered front wheels and the ability to power at least one rear wheel for added traction and control, as needed.
Additional objects, advantages and novel features of the invention will be set forth in part in the description as follows, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.